Ingestion of Ethyl alcohol (EtOH) interferes with gastric emptying in mammals. Little is known of the underlying mechanisms for this effect. In preliminary experiments we observed that EtOH (0.1-1%) inhibited contractile activity of muscles from the canine gastric antrum. This finding suggests the possibility that EtOH affects gastric emptying by interfering with excitation-contraction mechanisms of gastric muscle cells. General questions under investigation will be: i) What are the effects of EtOH on frequency, amplitude, and duration of gastric muscle contractions? ii) Are the mechanical effects of EtOH due to electrical mechanisms? The effects of EtOH on contractions of gastric muscles will be studied, in vitro, in prefused muscle chambers. An attempt will be made to determine whether EtOH acts directly on muscle cells or if its effects are mediated by intrinsic neurotransmitters or local regulatory agents. Parallel experiments will investigate the effects of EtOH on the electrical activity of single muscle cells to determine whether or not the mechanical effects can be explained by an electrical mechanism. The long-term effects of chronic intragastric EtOH administration on gastric muscles will also be studied to determine: i) Does chronic EtOH administration change electrical and mechanical activities of muscles? ii) Do gastric muscles "adapt" to chronically high EtOH levels? This proposal is unique because it combines sophisticated mechanical and intracellular electrophysiological techniques to study questions of clinical and social significance that have heretofore only been studied descriptively, in vivo. The results should significantly enhance our basic understanding of the consequences of acute and chronic EtOH consumption on gastric motor function.